Iron-Catalyzed, Site-Selective Difluoromethylthiolation (−SCF<sub>2</sub>H) and Difluoromethylselenation (−SeCF<sub>2</sub>H) of Unactivated C(sp<sup>3</sup>)–H Bonds in <i>N</i>-Fluoroamides
作者:Hongwei Zhang、Fei Yu、Chuang Li、Peiyuan Tian、Yulu Zhou、Zhong-Yan Cao
DOI:10.1021/acs.orglett.1c01443
日期:2021.6.18
The iron-catalyzed δ-C(sp3)–H bond difluoromethylthiolation and difluoromethylselenation of aliphatic amides with high site selectivity are reported. Essential to the success is the employment of an amide radical formed in situ to activate the inert C(sp3)–H bond and the utilization of the easily handled PhSO2SCF2H and PhSO2SeCF2H as coupling reagents under mild conditions. This scalable protocol exhibits
报道了铁催化的 δ-C(sp 3 )-H 键二氟甲硫基化和脂肪族酰胺的二氟甲基硒化,具有高位点选择性。成功的关键是使用原位形成的酰胺自由基来激活惰性 C(sp 3 )-H 键,并在温和条件下使用易于处理的 PhSO 2 SCF 2 H 和 PhSO 2 SeCF 2 H 作为偶联剂. 这种可扩展的协议展示了具有多功能功能组的广泛基板范围。机理研究表明,反应通过-SCF 2 H 和-SeCF 2 H 自由基转移进行。
Remote Directed Isocyanation of Unactivated C(sp<sup>3</sup>)–H Bonds: Forging Seven-Membered Cyclic Ureas Enabled by Copper Catalysis
site-selective δ-C(sp3)-Hbondsactivation of aliphatic sulfonamides for constructing the synthetically useful seven-membered N-heterocycles. A key to success is the use of in-situ-formed amide radicals, to activate the inert C(sp3)-H bond, and inexpensive TMSNCO, as a coupling reagent under mild conditions. To the best of our knowledge, this represents the first use of alkylamine derivatives as a five-membered
Regioselective synthesis of isoquinolinonediones through remote unactivated C(sp3)–H bonds
作者:Lei Huang、Jun Sun、Boxuan Sun、Shengjie Song、Jianjun Li
DOI:10.1039/d4cc00916a
日期:——
general strategy for the remote-site-selective cascade addition/cyclization of unactivatedC(sp3)–H bonds in free alcohols and sulfonamides to build isoquinolinonedione skeletons is developed. The site selectivity occurs predominantly via a 1,5-hydrogen atom transfer (HAT) process, triggered by heteroatom-centred radicals generated directly under silver catalysis. A broad substrate scope and excellent